goods=[
    ("iphone",5800),
    ("iwatch",2300),
    ("Huawei P9",4300),
    ("Mac Pro",12000),
    ("Book",500)
]########################商品列表
shoping_list=[]##########空表
salary=input("input You are Salary:")
if salary.isdigit():###########.isdigit整数
    salary=int(salary)#####转数据为int
    while True:####循环
        for index,item in enumerate(goods):########虚幻index，给goods赋值
            print(index,item)
        user_choice=input("please choice goods...")
        if user_choice.isdigit():
            user_choice=int(user_choice)
            if user_choice<len(goods) and user_choice>=0:
                p_item=goods[user_choice]
                if p_item[1]<=salary:
                    shoping_list.append(p_item)
                    salary-=p_item[1]
                    print("Added %s into shopping cart ,your current balanceis \033[31;1m%s\033[0m"%(p_item,salary))
                else:
                    print("\033[41;1m你的余额不住，只剩[%s]\033[0m"%salary)
            else:
                print("product code [%s] is not exist!" % user_choice)
        elif user_choice=="q":
            print("---------------shopping list------------------")
            for p in shoping_list:
                print(p)
            print("your current balance",salary)
            exit()
        else:
            print("invalid option")

购物车练习